PTPRD
PTPRD belongs to the LAR subfamily of receptor-type protein tyrosine phosphatases, whose members carry adhesion-like extracellular regions built from immunoglobulin-like and fibronectin type III domains, followed by tandem intracellular catalytic phosphatase domains. Best studied in the nervous system, PTPRD supports motor neuron survival and synaptic development, and genome-wide association studies have linked variation at the PTPRD locus to restless legs syndrome. The enzyme dephosphorylates STAT3 and thereby restrains STAT3-driven transcription, which underlies its frequent classification as a tumor suppressor; PTPRD deletions and inactivating mutations recur in glioblastoma, melanoma, lung cancer, and other malignancies. Recombinant PTPRD is valuable for phosphatase drug discovery, where the catalytic chemistry of the subfamily attracts inhibitor development.
